EJ25 Rebuild

[jread]

So I just got an ej25 to swap into my Subaru loyale. It's got 160k on it so I'm going to pull it replace the head gasket and timing belt.

 

Just wondering what is absolutely essential to the rebuild as I'm short on funds.

 

Head gasket felpro 3 layer is a must from what I understand

 

Timing belt for sure, hoping to avoid doing the tensioners or at least just replacing the bearings in them. I've got a bearing/ seal pusher. Saving 150 bucks seems worth it for the work just don't know if it will be as reliable.

 

What about water pump? Thermostat?

 

As for the rest I'll likely do

 

Intake manifold gasket

Valve cover gasket

Coolant manifold o rings

 

Anything I'm missing?

[1 Lucky Texan]

interference engine, risky on the 2.5 to not replace the rollers in the TB system. The toothed idler is 'especially' prone to failure.

 

you could test the thermostat on the stove, if it opens and closes smoothly at 170* F, re-use it. There is a Stant Xacstat that is OEM-style that is not crazy expensive.

 

spark plugs are a little easier if you're also doing the VC gaskets.

 

clean and re-use the PCV valve?

Edited November 19, 2015 by 1 Lucky Texan

[987687]

Only use an OEM thermostat, OEM on the right in this picture. If you have an aftermarket one, go to the dealer and get a new one, they're $15 or thereabouts.

 

 

I only use STi headgaskets, they're about $45/side and the best gaskets you can get for your engine (assuming you have a sohc 2.5).

 

REPLACE ALL THE IDLERS, TENSIONER, AND WATERPUMP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I had a waterpump seize on me once, fortunately it wasn't an interferance engine, so no engine damage. I had 3 friends in the car on the way to a concert we paid for and didn't get to see because I was a cheapass and didn't buy a $25 part. It would have been cheaper to buy a stupid waterpump than 4 concert tickets and towing 50 miles home.... The same can happen with any of the idlers.

[AdventureSubaru]

x2. Don't skimp on the idlers.

 

On these motors best to do a head resurfacing. There's a DIY writeup to use glass and sand paper for it, or find a decent machine shop.

 

Not sure if Felpro were still the same as Fuji for the MLS gaskets. They certainly were for the 90-98 EJ22, not sure about the EJ25

[Caboobaroo]

I would steer clear from the Fel Pro MLS gaskets. Metal is way too thin, coating is crap and comes off in about 20k miles. If to want to do it once, get Six Star or OEM Subaru turbo head gaskets.

[ocei77]

The Stant Xactstat #48457 is exactly the same as Subaru's unit.

 

O.

[upnorthguy]

On these motors best to do a head resurfacing. There's a DIY writeup to use glass and sand paper for it, or find a decent machine shop.

 

The DIY is the post-apocalytic method here.

Edited November 19, 2015 by upnorthguy

[upnorthguy]

 Anything I'm missing?

 

Check the oil separator plate for metal/non-metal.  If metal, reseal.  If not metal, install metal.  Plus replace the wrist pin access o-ring next to it.

Tighten the oil pump screws/change o-ring.

[jread]

OK so I know now for sure don't skimp on idlers but is doing the bearings myself not going to be as good as getting them pre done? It takes more time yes but I enjoy doing that more than my job!

[987687]

OK so I know now for sure don't skimp on idlers but is doing the bearings myself not going to be as good as getting them pre done? It takes more time yes but I enjoy doing that more than my job!

 

I guess if you wanna track down the bearings and press them yourself, go ahead. At least 2 of them have dual bearings, so by the time you buy all the bearings and screw around with it... eh. I tend to spend $20 to get something that I know was done right from the factory than spend $15 and waste several hours reinventing the wheel. But new bearings are new bearings, so go ahead.

 

Speaking of that head surface guide, where ever did GD go? 

Edited November 20, 2015 by 987687

[jread]

So I found a sticker today that indicates the belt was changed at 113k I'm now at 167k. Still going to replace the thing since I don't know if they did the rest of the job...

 

I didn't know that lots of them were doubled that definitely decreases the savings margin.

 

ALSO just realized rock auto shows me Canadian pricing not US. I thought I had to add another 30% to prices. 270 cad is better than 360!

 

Going to grab the full gates kit from RockAuto

 

Now onto HG questions. What model # am I looking at for a turbo gasket?

 

I looked at those six star kits but $300? Seems like a lot. Is there any gaskets one would replace above these? Seems like it covers everything mentioned here except the oil separator. https://allwheeldriveauto.com/product/1996-1999-subaru-legacyoutback-dohc-head-gasket-kit/

 

Is sixstar really necessary and worth it? or can I go with something more modest?

 

Love that resurfacing guide going to save a bunch there!

[jread]

Also what does everyone vote on new head bolts? Yay or nay? Feel pro ones fine or spring for the six star?

[idosubaru]

do not replace headbolts, no vote is needed, it's a fact.  people that say replace them are OCD, just borrowing ideas from other platforms/manufacturers, always have and always will, or armchair quarterbacking.  no dealer replaces them, no one that has done significant Subaru work for decades on many motors replaces them.  it's obvious.

 

GD is very busy, that's all.  

 

1.  resurface the heads (view link above, you can do it yourself, it's really easy).  they always have high and low spots, don't even test them.  

2.  if it's a DOHC EJ25 - use the Subaru Turbo EJ25 headgaskets. 

 

the tensioner really needs replaced - not just for the bearings but for the hydraulic mechanism.  

have you checked amazon for the Gates timing belt kit?

 

there's no need for kits if you're trying to keep costs low- just buy what you need, not a $300 engine kit.

 

if funds are short i wouldn't replace the water pump, they rarely have issues and catastrophic failure is nearly unheard of.   i wouldn't replace the thermostat either.

 

i'm the oddball on this but for all the talk abuot thermostats - i've yet to see a failed Subaru thermostat, or even aftermarket, I'd just leave yours until you have issues.  i think thermostats get replaced all the time as a first, cheap, easy step - and that almost perpetuates the notion they often cause issue when they really don't.   start driving 200,0000 miles without replacing one and i'll bet we'd see very few failures - i haven't.  granted they're cheap so it doesn't really matter - but the thing either opens or not, i'll wait until it doesn't open to replace one - so far i'm at 200,000 miles lots of times and never replaced one and routinely have friends/family that don't care about cars/maintenance and never do anything but oil/air filter for 150,000+ miles and they never replace them....whatever they're failure rate is, it's not big.  but i understand the notion of replacing them and often have if it's for other people or cetain cars other than my own, for those i routinely replace them as a matter of caution.

 

subarupartswarehouse.com and others are 20% cheaper than Subaru dealers and ocassionally, around holidays, have big sales.  they've had like 30% off for Halloween recently. if you're buying the EJ25 Turbo headgaskets.

[987687]

I still don't know if you have a single cam or dual cam motor.... If it's a single cam 2.5, the STi headgaskets to use are subaru part number 11044AA642.

 

If you have a dual cam, those won't work. Head bolts are a good idea if you're building a high hp turbo engine... otherwise make sure they have a light coating of oil on the threads and washers during installation. And headgaskets go on dry. Mating surfaces perfectly clean, no sealer, no nothing.

[ocei77]

The turbo gasket ending in 642 will work on the ej25D.

 

O.

[DaveT]

I've had good results rebuilding the idlers on my ea82 engines. Made rebuildable tensioners. I go to a local bearing supply shop. Order bearings with contact seals, and high temperature grease. Big name brand name only, no made in China crap. The whole interference engine thing does add a layer of nervous to the idea.

[AdventureSubaru]

I second the water pump omission. Yet to see one fail.

 

I keep a spare used thermostat in my car as a "just in case" but also have never seen a failed subaru thermostat in normal circumstances. The one I ever HAD to replace was gunked up from someone applying blue devil head gasket sealer without pulling the thermostat or properly idling the motor. Cost them a new thermostat and radiator and the head gaskets still leaked.

[jread]

Oh man new levels of confusion added! 

 

Water pumps have votes for and against but its only $25 difference in the two kits and in the area so seems silly not to just do it because of fear!

I'm almost leaning towards the Six Star HG because its well recommended and I have to give them a vin so it won't be a codswallop up. Will probably just get this from them and the rest of the gaskets from Rock Auto. For everything but the HG would you guys go Felpro or Victor Reinz? I've herd VR for Exhaust and intake as they use graphite, anyone disagree?

 

Headbolts are out - great

[987687]

Just get the STi gaskets... I posted the part number. I know they work fine with the 00-04 sohc 2.5 engines, because I've put them in that year range vehicles. ocei77 says they'll also work in the dohc engines, which I did not know, good information.

[jread]

Got most of the way through the rebuild really no problems with any of it but glad I checked. Have new Tbelt, water pump, HG, Intake gaskets, exhaust gaskets, fuel and oil filter.

Now I'm losing my mind at the beginning of the build I flipped one of the heads and the buckets started falling out on the table. I already lost track so just said screw it and just kept them separated left and right.  I've been reading how to measure and figure out the shims but I just can't get them all within spec. I can get most but not all. is +- .02mm crucial or can I go to .03?

 

Do I need to press them in somehow to make sure they are sitting properly? Is it likely they just went out over time? I figured if things were wearing out they would gain clearance but I'm mostly having an issue with not enough clearance. Are the buckets also different sizes? Hard to measure the tiny nub on the inside... Any tips at all?

The engine was running when I got it, figured it would have problems but really everything was great. Really wish I had just done head gaskets and timing belt and called it a day but really wanted to be thorough

[1 Lucky Texan]

no experience here, but from reading, the valves stretch over time - I guess they also sit slightly deeper in the seats - anyway, exhaust valves evidently get longer/less clearance. You can , carefully, grind the back of a shim down, just put the ground side away from the wear of a cam.

[jread]

Definitely not grinding away without the proper tools. I'm really wondering if its a big deal if they are out a little extra... On the exhaust side. The engine ran before so it should be fine now and realistically this will just push the valve open a little extra? But maybe also a touch early I guess...

[1 Lucky Texan]

well, you could lap a shim on some wet-dry over a piece of glass and do pretty well.

 

Or figure out what shims you need and order them. You may only need a couple after you swap them around ???

 

If they are too tight, I think the danger is, the valve may not close completely at operating temp and would burn an edge.

[joomanburning]

Do all Tbelt idlers. If it's a 5spd make sure to set the crank pulley guide at the proper height. Gates makes a spacer tool for this exact thing, their kit is awesome, I highly recommend it. I just pulled 16 bent valves outta a SOHC EJ25 Forester I bought, water pump seized... and I also had to re-belt my 99 OBS because I was unaware my guide was too close to the crank pulley and it was shredding the backside of the belt. Timing is everything.

[1 Lucky Texan]

wow - not sure I've read of a seized water pump before.